The Davenport province, situated between the Proterozoic Tennant Creek Au-Cu- Bi metalliferous province and Arunta Inlier, consists of sedimentary, volcanic and intrusive rocks which are overlapped by flat-lying Palaeozoic sediments of the Georgina and Wiso Basins. The oldest rocks seen are turbiditic sediments and subordinate chert and felsic volcanics of the 1870 Ma-old Warramunga Group. This group, which is exposed only in the north, was folded, weakly metamorphosed, intruded by granite, and eroded before being overlain by the Hatches Creek Group, the main component of the Davenport province. The Hatches Creek Group is a folded sedimentary and bimodal volcanic sequence, at least 10 km thick, comprising three subgroups, twenty formations, and two named members; felsic volcanics in the oldest subgroup were probably erupted 1810-1820 Ma ago. The group is correlated with part of the Tomkinson Creek beds north of Tennant Creek and probably with Division 3 of the Arunta Inlier. The sedimentary rocks include quartz-rich to lithic and feldspathic sandstone, conglomerate, siltstone, finer-grained rocks, and minor carbonates, some of which are stromatolitic. Environments were mainly fluvial (alluvial fan, braided stream, meandering stream) in the lower part of the group and shallow marine (including tidal) in the middle and upper parts. Felsic and mafic volcanism, comagmatic sill emplacement, and probably faulting accompanied sedimentation, which kept pace with subsidence. An extensional ensialic tectonic setting is envisaged. The sequence was deformed, regionally metamorphosed to mainly greenschist facies, and subsequently intruded by 1660 Ma-old granite. The deformation was of thick-skinned type, and involved two episodes of tight, upright, concentric folding. Chemically, the felsic volcanics of the Hatches Creek Group differ from those of the Warramunga Group (which resemble the 1865 Ma-old Leichhardt Volcanics in the Mount Isa Inlier) in having higher contents of Ti, P, Th, U and especially Zr, Nb and Y, and lower Ca, AI, Sr and V. The mafic volcanics of the Hatches Creek Group are continental tholeiites. Geophysical data show that the younger granites of the province correspond to marked gravity lows; that units within the Hatches Creek Group can be traced in the subsurface using contoured aeromagnetics; and that the felsic igneous rocks are moderately radioactive. Mineralisation is largely restricted to the lower part of the Hatches Creek Group, where there are quartz veins with wolframite and scheelite probably related to granite intrusions, and auriferous quartz veins that may have formed during regional metamorphism. Total recorded production amounts to about 4500 t tungsten concentrates, mainly from the Hatches Creek and Wauchope tungsten fields, and 15 kg gold. Small quantities of copper, silver-lead, bismuth, and uranium have also been mined.
